So things did not go very smoothly. The Valvetronic exhaust pipe is 63.5mm in diameter. The inlet diameter for these tips ranges from 68-73mm. So there was a good 4.5mm+ gap.
I've done a very temporary fix - I wedged some screws between the exhaust pipe and the tip inlet and then clamped down on that hard. They're on there sturdy, but eventually I'll need to do something more permanent like weld some metal to the exhaust pipes to increase the diameter a bit.
BEFORE: these are the 3.5" chrome tips that come with the Valvetronic exhaust:
AFTER: The AA 4" tips. Still need to align them better but will do so when I get the permanent fix in place.
